ITPub博客

首页 > Linux操作系统 > Linux操作系统 > 10G DataGuard筆記

10G DataGuard筆記

原创 Linux操作系统 作者:xhailiang 时间:2008-11-17 16:14:45 0 删除 编辑
LOG_ARCHIVE_DEST_n PARAMETER'S ATTRIBUTE
LGWR
ARCH
¡½ Specifies whether redo transport services use archiver processes (ARCn) or the log
writer process (LGWR) to collect transaction redo data and transmit it to standby
destinations. If neither the ARCH or LGWR attributes are specified, the default is ARCH.
SYNC
ASYNC
¡½ Specifies that network I/O is to be done synchronously (SYNC) or asynchronously
(ASYNC) when archival is performed using the log writer process (LGWR).
MANDATORY
OPTIONAL
Specifies the policy for reusing online redo log files:
¡½ MANDATORY¡Xspecifies that filled online log files must be successfully archived to
the destination before they can be reused.
¡½ OPTIONAL¡Xspecifies that successful archival to the destination is not required
before the online redo log file can be made available for reuse.
AFFIRM
NOAFFIRM
¡½ AFFIRM¡Xspecifies that all disk I/O to archived redo log files and standby redo
log files is performed synchronously and completes successfully before the log
writer process continues.
¡½ NOAFFIRM¡Xspecifies that all disk I/O to archived redo log files and standby redo
log files is performed asynchronously; the log writer process on the primary
database does not wait until the disk I/O completes before continuing.
REOPEN
MAX_FAILURE
¡½ REOPEN Specifies the minimum number of seconds before redo transport services should try to
reopen a failed destination.
¡½ MAX_FAILURE Controls the consecutive number of times redo transport services attempt to
reestablish communication and transmit redo data to a failed destination before the
primary database gives up on the destination.
LOCATION
SERVICE
¡½ Each destination must specify either the LOCATION or the SERVICE attribute to
identify either a local disk directory or a remote database destination where redo
transport services can transmit redo data.
DB_UNIQUE_NAME
¡½ Specifies a unique name for the database at this destination.

VALID_FOR
Specifies when redo transport services transmit redo data to a destination, based on
the following factors:
¡½ Whether the database is currently running in the primary or the standby role
¡½ Whether online redo log files, standby redo log files, or both are currently being
archived on the database at this destination
VALID_FOR Definition Primary Role Physical Standby Role Logical Standby Role
ONLINE_LOGFILE, PRIMARY_ROLE Active Inactive Invalid
ONLINE_LOGFILE, STANDBY_ROLE Inactive Invalid Active
ONLINE_LOGFILE, ALL_ROLES Active Invalid Active
STANDBY_LOGFILE, PRIMARY_ROLE Error Error Error
STANDBY_LOGFILE, STANDBY_ROLE Invalid Active Active
STANDBY_LOGFILE ALL_ROLES Invalid Active Active
ALL_LOGFILES, PRIMARY_ROLE Active Inactive Invalid
ALL_LOGFILES, STANDBY_ROLE Invalid Active Active
ALL_LOGFILES, ALL_ROLES Active Active Active

Minimum Requirements for Data Protection Modes

Maximum Protection  Maximum Availability Maximum Performance
Redo archival process LGWR LGWR LGWR or ARCH
Network transmission
mode
SYNC SYNC SYNC or ASYNC when using
LGWR process. SYNC if using
ARCH process
Disk write option AFFIRM AFFIRM AFFIRM or NOAFFIRM
Standby redo log required? Yes Yes No, but it is recommended


CHANGING THE PROTECTION MODE
PERFORM. THE FOLLOW STEP ON PRIMARY DATABASE
STEP 1:
SQL> SHUTDOWN IMMEDIATE;
SQL> STARTUP MOUNT;
STEP 2:
ALTER DATABASE SET STANDBY
DATABASE TO MAXIMIZE {PROTECTION | AVAILABILITY | PERFORMANCE}
SQL> ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE AVAILABILITY;
STEP 3:
ALTER DATABASE OPEN;
STEP 4:
Configure the LOG_ARCHIVE_DEST_n parameters
STEP 5:
CONFIRM THE CONFIGURATION
SQL> SELECT PROTECTION_MODE, PROTECTION_LEVEL FROM V$DATABASE;

 

 

 

来自 “ ITPUB博客 ” ,链接:http://blog.itpub.net/308563/viewspace-496147/,如需转载,请注明出处,否则将追究法律责任。

上一篇: running on empty
下一篇: wwww
请登录后发表评论 登录
全部评论

注册时间:2008-02-17

  • 博文量
    270
  • 访问量
    423387